The effects of chemicals found in the environment, both on man and animals, is of widespread concern. The history of chemical regulation in the United States is one of increasing stringency in terms of what is "acceptable" in the environment and the workplace. Fueled by an ever-expanding body of scientific knowledge, and supported by public outcry for a "clean environment," and labor and management's interest in a cleaner, safer workplace, the demand for ability to detect environmental contaminants, and aromatic hydrocarbons in particular, and to determine how much of such substances are present in the environment, is rapidly growing.
Certain aromatic hydrocarbons, e.g., benzene, toluene, and xylene, have a broad basis of application and utilization as solvents and additives. Benzene is present in the workplace in the chemical manufacturing industry as well as industries involved in industrial manufacturing of motor fuels, inks, oils, paints, plastics, and rubber. Additionally, the materials are used in manufacturing detergents, explosives, pharmaceuticals, and dye stuffs. The National Institute of Occupational Safety and Health estimates that over two million workers in the U.S. are potentially exposed to benzene, a known cause of leukemia in humans.
Furthermore, benzene is present and its uses are enhanced in unleaded fuels for automobiles equipped with catalytic converters. Thus, benzene is a persistent and notable constituent of gasoline. Gasoline is currently leaking from an existing half million or more underground storage tanks in the U.S. Hence, the ability to detect benzene in potable water by a rapid method becomes of increasing value in assessing the presence or absence of gasoline contaminants of water supplies.
Toluene and xylene are also present in the workplace and in some petroleum fuels. Many other aromatic hydrocarbons, e.g. including chlorinated derivatives of benzene, toluene and xylene, naphthalene, styrenes, etc. are found in various environmental milieus.
At present, systems for determining the presence of aromatic hydrocarbons in the workplace and the environment include gas chromatography, mass spectrophotometry and high performance liquid chromatography.
In general, these current methods for analysis require a collection of samples of air, water, soil, etc., transportation of the sample to an analytical laboratory, and an analysis by professionals using costly equipment and reagents. The results obtained must then be transmitted back to the entity that ordered the testing. This process is expensive and time-consuming.
Thus, alternative testing procedures for aromatic hydrocarbons and their derivatives which are simpler, less expensive, and adaptable to being rapidly carried out on-site are being needed.